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SQL UPDATE SET one column to be equal to a value in a related table referenced by a different column
...result set to update is before running the update (same query, just with a select):
select *
from QuestionTrackings q
inner join QuestionAnswers a
on q.AnswerID = a.AnswerID
where q.QuestionID is null -- and other conditions you might want
Particularly whether each answer id has definitely only 1...
How to “add existing frameworks” in Xcode 4?
...
As per Apple's documentation:
In the project navigator, select
your project.
Select your target.
Select the "Build Phases" tab.
Open "Link Binaries With Libraries"
expander.
Click the + button.
Select your framework.
(optional) Drag and drop the added
framework to the "Framework...
'git' is not recognized as an internal or external command
...
In the Start Menu or taskbar search, search for "environment variable".
Select "Edit the system environment variables".
Click the "Environment Variables" button at the bottom.
Double-click the "Path" entry under "System variables".
With the "New" button in the PATH editor, add C:\Program Files\Gi...
How to check if a database exists in SQL Server?
...script:
DECLARE @dbname nvarchar(128)
SET @dbname = N'Senna'
IF (EXISTS (SELECT name
FROM master.dbo.sysdatabases
WHERE ('[' + name + ']' = @dbname
OR name = @dbname)))
-- code mine :)
PRINT 'db exists'
share
...
Maven2: Best practice for Enterprise Project (EAR file)
...
What helped me a lot was to run the Maven archetype:generate goal and select from one of the archetypes, some of which seem to be updated regularly (in particular JBoss seems to be well maintained).
mvn archetype:generate
Hundreds of archetypes appeared in a numbered list from which to selec...
How do I change Eclipse to use spaces instead of tabs?
...dow » Preferences
Expand Web » HTML Files
Click Editor
Under Formatting, select the Indent using spaces radio button
Click OK to apply the changes.
CSS
Follow the same instructions for HTML, but select CSS Files instead of HTML Files.
JSP
By default, JSP files follow the formatting preference...
How do I kill all the processes in Mysql “show processlist”?
...peration saves time. Do it in MySql itself:
Run these commands
mysql> select concat('KILL ',id,';') from information_schema.processlist
where user='root' and time > 200 into outfile '/tmp/a.txt';
mysql> source /tmp/a.txt;
Reference
---------edit------------
if you do not want to sto...
What GRANT USAGE ON SCHEMA exactly do?
...a schema doesn't grant rights on the tables within.
If you have rights to SELECT from a table, but not the right to see it in the schema that contains it then you can't access the table.
The rights tests are done in order:
Do you have `USAGE` on the schema?
No: Reject access.
Yes: Do...
How do I delete a fixed number of rows with sorting in PostgreSQL?
...
You could try using the ctid:
DELETE FROM logtable
WHERE ctid IN (
SELECT ctid
FROM logtable
ORDER BY timestamp
LIMIT 10
)
The ctid is:
The physical location of the row version within its table. Note that although the ctid can be used to locate the row version very quickly,...
Concatenate multiple result rows of one column into one, group by another column [duplicate]
...Simpler with the aggregate function string_agg() (Postgres 9.0 or later):
SELECT movie, string_agg(actor, ', ') AS actor_list
FROM tbl
GROUP BY 1;
The 1 in GROUP BY 1 is a positional reference and a shortcut for GROUP BY movie in this case.
string_agg() expects data type text as input. Other ...